U.S. Launches Two Experimental Missile Defense Satellites

by SPACE.com Staff | September 25, 2009 05:59pm ET

The United Launch Alliance Delta II rocket with Space Tracking and Surveillance System - Demonstrator, or STSS-Demo, spacecraft aboard races into the sky leaving a trail of fire and smoke after liftoff from Launch Pad 17-B at Cape Canaveral Air Force Station.Credit:

A
NASA-managed rocket launched two experimental satellites designed to track ballistic missiles Friday in a test flight for the United States Missile
Defense Agency.

The Delta 2
rocket blasted off at 8:20 a.m. EDT (1220 GMT) from the Cape Canaveral Air Force
Station in Florida carrying two Space Tracking Surveillance System (STSS) satellites on a
technology demonstration mission. They reached orbit just under an hour later.

"With
confirmation of the payload's delivery into the correct orbit, the launch is a
success," said Omar Baez, launch director for NASA?s Launch Services
Program headquartered at Kennedy Space Center, in a statement. The launch was
delayed by two days due to weather and technical glitches.

The two STSS
demonstration satellites form part of the Missile Defense Agency?s layered
Ballistic Mission Defense System. They are designed to demonstrate the ability
of tracking ballistic missiles in every stage of flight, something U.S.
space-based assets cannot currently do.

"The STSS DEMO mission is important to our
nation's defense,? said Air Force Brig. Gen. Edward L. Bolton Jr., 45th Space Wing
commander. ?Our team continues to work hard to ensure we are doing all we can
to provide the support needed for such important missions to occur."

The
satellites were originally built by Northrop Grumman for an earlier flight
demonstration program that was scrapped in 1999. The project was revived in
2002 when the Missile Defense Agency (MDA) awarded Northrop Grumman an $868 million contract to ready the satellites for launch.
To date, $1.5 billion have been spent on the project.

"Even
though the hardware was built in the 1990s, when the two STSS
demonstrators are on orbit, they will bring a
unique capability to the MDA," Gabe Watson, Northrop Grumman's STSS
program manager, told SPACE.com in June. "We can track missiles in every
stage of flight, from launch to intercept, and do hit assessment as well. If
the MDA wants to intercept missiles in the ascent phase, they will need
additional data that [current missile warning satellites] don't provide."

The STSS
satellites follow NASA?s launch of another missile
defense satellite - the STSS Advanced Technology Risk Reduction spacecraft -
in early May. They weigh about 5,000 pounds (2,267 kg) and are equipped with a
staring sensor similar to those used on other Air Force defense satellites. But
they also carry a multi-band infrared sensor to track missiles.

At least
two tests of the STSS system are planned using dedicated missile launches to
check the satellites? performance. They may also play a role in two other tests
with other defense systems such as the Aegis Ballistic Missile Defense system, STSS
program officials have said.

The new
STSS satellites are expected to undergo a three-month checkout phase by
Northrop Grumman, which will operate them from the Schriever Air Force Base in
Colorado. A six-month test period is expected to follow.

Congress
has not yet approved any funding for an operational version of the missile
defense satellites, though military officials may pursue funds to begin that
work in 2011 if the STSS demonstration satellites prove to be effective.